An increasingly preferred method of installing insulation into a building or residential structure is the method of "blowing in" or spraying insulation particles mixed with adhesive into the space between the outer and inner walls of the structure. The aggregate of insulation particles and the adhesive is commonly referred to as loose fill insulation. The outer walls of the structure are typically composed of concrete, masonry, metal or alloy sheeting or wood. The inner walls are typically composed of drywall, paneling or plaster mounted on a backing. The outer walls may be mounted on the same support skeleton which supports the inner walls or they may be mounted on a separate support skeleton.
The construction sequence calls for the outer walls to be installed before the inner walls. Prior to the construction of the inner walls, it is desirable to "blow in" the loose fill insulation so that no access holes need be placed in the inner walls once they are constructed. However, prior placement of the insulation requires the use of some means to retain the insulation between the wall framing until the inner wall can be constructed to act as a retaining barrier.
The patent to Walls et al. (U.S. Pat. No. 4,385,477), discloses a method for attaching heat shrinkable material to the wall framing and then blowing in particulate insulation through selected holes in the heat shrinkable material. However, there are several drawbacks associated with the use of heat shrinkable material. First, the material presents an impermeable barrier which prevents the escape of air which is displaced during the installation of the blown-in particles. It is desirable to allow displaced air to escape during the installation process so as to facilitate uniform compaction of the particles. Secondly, the method calls for covering the entire area between adjacent wall and ceiling supports with the heat shrinkable material. It is desirable to reduce the amount of material required for the installation of insulation particles prior to construction of the inner walls.
The invention disclosed in the patent to Story (U.S. Pat. No. 4,292,777) is directed to a system for supporting blowable insulation installed in a horizontally extending frame. A rectangular cardboard sheet with perpendicularly disposed tabs is positioned between two adjacent joists and attached to the joists. The particulate insulation is sprayed into the space between the cardboard sheet and the finished ceiling or floor. However, the Story invention fails to disclose the use of netting or any method of determining that sufficient insulation material has been blown in so as to achieve a desired density of insulation. The cardboard includes a relatively few number of holes and is more expensive than netting. The cardboard sheet disclosed in the Story patent is also constructed with a fixed width so that adjustments must be made to install the cardboard sheet between joists which are spaced apart at a non-customery width.